Process of producing milk-powder.



UNITED STATES ATENT OFFICE.

HENRY V. DUNHAM, OF NEW YORK, N. Y.

PROCESS OF PRODUCING MILK-POWDER.

SBEOIFICATION forming part of Letters Patent No. 723,254, dated March 24, 1903.

Application filed August 11,1902. Serial No. 119,193. (Specimens) To all whom zit may concern.-

ing Milk-Powder, of which the followingis a specification, reference being had therein to the accompanying drawings.

In the production of milk-powder manyattempts have been made to utilize skimmed as well aswholemilk to procure a powderwhich shall possess the propertyof dissolving read ily in warm water into the original consistency of fresh. milk andwhich shall have the peculiaropacity and qualities of suspension which are characteristi of fresh milk. Milkpowder .has been produced by the vacuum pan process and condensation process to reduce the milk to a dry powder; but the results obtained from this vacuum-pan process have been unsatisfactory, for the reason that the product is an insoluble one, is not held in suspension, and, quickly settles when mixed with water, sothat it lacks the qualities and opacity of fresh milk. In another process known to me milk-powder has been produced by blowing warm air into the milk until a heavy consistencyor thickening of the milk results and then drying out the resulting compound by means of warm air in a series of revolving drums or driers. This process, while superior to the vacuum pan process mentioned above, is imperfect in results and unsatisfactory because of the fact that it requires a great deal of time, is quite expensive, and the milk-powder producedis more or less insoluble.

The object of my present invention or discovery is the production of a desiccated milkpowder from whole or skimmed milk which is perfectly soluble and which when diswhich degree of heat is maintained for from twenty minutes to half an hour. it is preferable to do thisheating by blowing the steam through the milk, for the reason that by using steam any disagreeable odors present are driven from the milk and entirely eliminated; but, as noted above, any other suitable heating means may be employed. I have discovered thatthe milk being in a very dilute solution is but slightly, if at all, aliected by this degree of heat, that such high temperature does not coagulate the albumen of the milk and render the product insoluble, and that the milk thus treated is condensed to a marked degree without producing the cooked odor and taste which is characteristic of many of the other milk-powders with whichlam familiar. After the milk has been heated, as described above, for about half an hour it is cooled as quickly as possible by running it over refrigerating-pipes, and this cooling step also overcomes in a marked degree the cooked odor and taste resulting from raising the milk to this high temperature. In cooling the milk I preferably reduce the temperature to about 90 Fahrenheit,although it is not absolutely essential that the milk be brought to as low a temperature as this. The milk after being thus cooled is drawn into vacuum-pans and condensed therein at a temperature of about 100 to 110 Fahrenheit to a density ofapproximately 23 Baum. When the milk has been condensed to the proper density in the vacuum-pans, it is drawn off and is then mixed with previouslyprepared milk-powder or any other suitable absorbent material, so as to take up the moisture in excess in the condensed milk and form a mass, which may then be broken up into small pieces and thoroughly dried by any suitable means. I find that it is preferable to use about equal parts of the milk which is condensed in the vacuum-pan. and the milk-powder or other similar soluble absorbent material with which it is mixed to form the mass. After the condensed milk has been thoroughly absorbed by the powder or other absorbent material which is mixed with it the mass is preferably spread upon screens of muslin and subjected to a drying temperature of about 140 Fahrenheit, al-- though any other suitable manner of drying the mass may be adopted. After the prod- I find that uct has been thoroughly dried itis removed from the screens or other drying instrumentalities and ground to a very fine powder.

Having thus described my invention or discovery, I claim and desire to secure by Letters Patent- 1. The herein-described steps in the process of producing milk-powder from whole or skimmed milk, consisting in heatingthe milk to about 200 Fahrenheit, then rapidly cooling it by a refrigerating process, and then condensing it at a temperature of about 110 Fahrenheit, to a density of about 23 Baum.

2. The herein-described process of producing niilk-powderfrom whole or skimmed milk, consisting in heating the milk to about 200 Fahrenheit, then rapidly cooling it bya refrigerating process, then condensing it at a temperature of about 110 Fahrenheit, to a density of about 23 Baum, then mixing the condensed product with an absorbent agent to take up excess of moisture, and finally drying the resulting mass and reducing it to powder.

3. The herein-described process of producing milk-powderfrom Whole or skim med milk, consisting in heating the milk to about 200 Fahrenheit, then rapidly cooling it by a refrigerating process, then condensing it at a temperature of about 110 Fahrenheit, to a density of about 23 Baum, then mixing the condensed product with approximately equal parts of prepared milk-powder to take up excess of moisture, and finally drying the resulting mass and reducing it to powder.

4:. The herein-described process of'producing milk-powderfrom Whole or skimmed milk, consistingin blowingsteam through the milk to eliminate the odors and raise it to a temperature of about 200-Fahrenheit, then cooling the milk quickly, then condensing'it in vacuum-pans at a temperature of about 110 Fahrenheit, to a density of about 23 Baum, then mixing the condensed product with approximately equal parts of prepared milkpowder to take up excess of moisture, then drying the resulting mass, and finally reducing the product to a fine powder.

In testimony whereof I affix my signature in presence of two witnesses.

HENRY V. DUNHAM.

VVitn esses:

S. LISTOE, J OHANNES D. Fi'IHRING. 

